Isiah Thomas held preliminary discussions Wednesday with the Nuggets about ex-Knick center Marcus Camby, whom Thomas selected with Toronto’s No. 2 pick of the 1996 draft, The Post has learned.

Thomas is searching for an athletic big man after losing Antonio McDyess in the deal, with Rasheed Wallace high on the wish list.

Camby has stayed relatively healthy this season, missing just four games. But he can opt out of his contract after the season, and the Nuggets could be concerned he’ll be asking for too much. Denver is again trying to get under the cap this summer.

“I think the Nuggets are more likely to extend him than trade him,” a source close to Denver GM Kiki Vandeweghe said.

In return, the Nuggets would want back a center and an expiring contract. They have interest in Michael Doleac, whose contract expires this summer, but don’t consider him a starter and would need more assets in a package. The source said a third team would likely be needed to make Camby a Knick again.

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The Post has obtained the fine details of the heavily protected future first-round pick the Knicks have given Phoenix.

The Suns can’t touch it until 2006. The Knicks keep it if they are 25th or better in the draft order. In 2007, they keep it if they are 24th or better. In 2008, they keep it if they are 23rd or better. The kicker is if the Knicks still have it by 2010, it goes to Phoenix, unprotected.

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Don Chaney scoffed at suggestions that 7-2 Polish center Cezary Trybanksi, 23, is similar a prospect to the recently cut 7-5, Slavko Vranes. Trybanski made his Knick debut last night, playing the final three minutes, missing his lone shot but getting cheered.

“He’s much more advanced than Vranes,” Chaney said. “Not even close.”

After last night, Doleac and Michael Sweetney can come off injured list with Trybanski going on it.

Ex-Knick assistants Tom Thibodeau and Steve Clifford and ex-Knick advance scout Andy Greer also made their return. The threesome declined contract-extension offers early last season and, predictably, ended up with Jeff Van Gundy. Chaney got a new staff with Brendan Malone and Lon Kruger.

“You work with guys you feel comfortable with,” Chaney said.

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How hot is Isiah Thomas? He’ll be David Letterman‘s guest Tuesday, joining actor Jeff Daniels on the “Late Show.”

Funny how former GM Scott Layden never made the late-night talk-show circuit. There’s no truth the “Top 10” list will be Layden’s worst player transactions.